This invention relates generally to the field of devices used to contain liquids, and especially such devices used as secondary containment to capture spills or run-offs of hazardous or non-environmentally-friendly liquids. More particularly, the invention relates to such devices which comprise a unified bottom and side walls to define a relatively large volume reservoir. Even more particularly, the invention relates to such devices which are collapsible and foldable into a relatively flat configuration for storage or transport, which can be rapidly and easily assembled or disassembled by the insertion or removal of brace members into or from flaps or pockets mounted onto the side walls, and where selected brace members can be removed from a portion of a side wall to allow a single side wall to collapse so that vehicles can be driven into the containment device.
There are numerous circumstances where it is desirable or required by law to contain certain hazardous liquids to prevent the liquids from entering the environment. For example, any spillage of liquids such as gasoline, oil, detergents, chemicals or the like during loading and unloading operations between liquid transport vehicles and storage tanks, during vehicle clean-up operations, or during vehicle fueling, must be captured and properly disposed of. Most locations where these events occur have no permanent recapture structures or systems, so it is necessary to provide a walled containment apparatus which is sufficient in size to allow a vehicle, such as a large tanker truck, to be positioned within its walls. Means to allow the vehicle to enter and exit the containment apparatus must also be provided. In general, apparatuses of this nature comprise pool-like structures, and typically are either fully rigid, have flexible walls of sheet material and gate means, have flexible walls and compressible wall support means, or have flexible walls and deformable or collapsible wall support means.
For example, U.S. Pat. No. 5,478,625 to Wright, shows a rigid containment device. Double-sided ramps at each end of the device enable a vehicle to be driven into and out of the device. An early collapsible container having flexible side walls and hinged grace members is shown in U.S. Pat. No. 92,364 to Rider. U.S. Pat. No. 5,547,312 to Schmitz, Jr., shows a pool-like apparatus having a floor and side walls made of a flexible sheet material. The walls are supported by a rigid frame having a peripheral upper member and a gate is provided at one end which can be lowered and raised to provide entry and exit means for the vehicle. U.S. Pat. No. 5,464,492 to Gregory et al. shows a containment device with walls supported by a foam member which is compressed by the vehicle wheel and which rebounds to create the wall when the vehicle wheel has passed. U.S. Pat. No. 5,090,588 to Van Romer et al. shows a device made of a flexible sheet material, where the wall is supported by a combination of vertical members adjacent the wall, a peripheral upper member, and internal brace members mounted to the floor of the device. The vertical support members and wall flex when a wheel passes over, and the brace members pull the wall back into the upright position after the wheel has passed. U.S. Pat. Nos. 5,316,175 and 5,762,233 to Van Romer show flexible-walled containment devices where non-vertical bracing members contain internal stiffener members.
It is an object of this invention to provide an improved liquid containment device for capturing liquid spills, especially such an apparatus which is foldable or collapsible into a generally flat configuration for storage or transport. It is a further object to provide such an device which is composed of flexible, liquid-impermeable, sheet material joined or folded to create a floor and side walls, where said side walls are supported by a number of spaced, removable, externally-mounted, brace members with no need for a peripheral upper support member. It is a further object to provide such a device where the brace members are relatively stiff and hinged, each having a vertical component, which is removably inserted into individual pockets, slots or flaps in the side walls, and an angled component, which is connected to an external floor skirt extending from the side walls. These and other objects are accomplished as set forth below.